This invention relates to a process for image transfer by introducing an image donating sheet and an image receiving sheet into a processing solution and pressing together both sheets; it relates also to equipment or apparatus to carry out the process.
There are well-known processes for the transfer of an image from one sheet to another. In a typical example of such processes, silver compounds or dyes are transferred imagewise from a photosensitive sheet bearing a silver halide emulsion layer to an image-receiving sheet to form thereon a silver image or a colored dye image. In another example, as described in Japanese Patent Application No. 49,640/85, an exposed photosensitive sheet is subjected to etching-bleaching, then the remaining gelatin layer is colored with a desired dye, and the colored sheet is allowed to contact closely with any other sheet to transfer the dye image to the latter sheet. The transferred dye image can be further transferred to another image-receiving sheet. Hereinafter, a sheet from which an image is transferred is referred to as an image donating sheet N and a sheet to which an image is transferred is referred to as an image receiving sheet P.
In carrying out the image transfer two sheets are brought into face-to-face superposition, both sheets are introduced into a processing bath while being held apart and guided by means of a parting plate, then both sheets are pressed together by a squeegeeing roll which removes the excess processing solution, and the sheets are peeled apart after the image transfer has been completed under atmospheric conditions. This process is used widely, because it needs only a simple processor.
A principal difficulty encountered with a conventional processor is that of keeping both sheets precisely in relative position, i.e. in both the direction of movement and the transverse direction. High precision is required in positioning the sheets when a multi-color image is formed by the overlay of multiple image receiving sheets each carrying a transferred colored dye image. It would be very useful, therefore, if the requirement could be met using a simple processor.